Railway-traffic-controlling apparatus and electrical apparatus suitable for use therein



March 12, 1929. 1,704,736

P. H. GEIGER RAILWAY TRAFFIC CONTROLLING APPARATUS AND ELECTRICALAPPARATUS SUITABLE FOR USE THEREIN Original Filed Oct. 29, 1925 2Sheets-Sheet l wO M E. w fr Fig 4 a 1 K a a 3 E1 P #T f jl m,

March 12, 1929.

P. H. GEIGER RAILWAY TRAFFIC CONTROLLING APPARATUS AND ELECTRICALAPPARATUS SUITABLE FOR USE THEREIN Original Filed Oct. 29, 1923 2Sheets-Sheet INVENTOBZ supplied with current from a battery 9 PatentedMar. 12, 1929.

UNITED STATES PATENT OFFICE.

PAUL H. GEIGER, OF SWISSVALE, PENNSYLVANIA, ASSIGNOR TO THE UNION SWITCH&

SIGNAL COMPANY, OF SWISSVALE, PENNSYLVANIA, A CORPORATION OF PENNSYLVANIA.

RAILWAY-'1RAFFIC-CONTROLLING APPARATUS AND ELECTRICAL APPARATUS SUIT-ABLE FOR USE THEREIN.

Application filed October 29, 1923. Serial No. 671,368.

My invention relates to electrical apparatus, and particularly torailway traflic controlling apparatus suitable for use therein.

I will describe several forms of apparatus embodying 1n y invention, andwill then point out the novel features thereofin the claim.

In the accompanying drawings, Fig. 1 is a diagralnnmt ic view showingone form of electrical apparatusembodying my invention. Figs. 2 and 3are views showing modifications of the apparatus shown in Fig. 1 andalso embodying my invention. Fig. 4 is a view showing one form ofrailway traffic controlling system based on the combination shown inFig. 1 and also embodying my invention.

Figs. 5 and 6 are views showing railway traffic controlling systemsbased on the combination shown in Fig. 3 and also embodying myinvention.

Similarreferencc characters refer tosimilar parts in each of the severalviews.

Referring first to Fig. 1, the apparatus in the form here showncomprises two windings 2 and 3 connected in multiple andreversiblythrough a pole-ehanger. 8. Associatedwith winding 2 is a device A- whichconstitutes means for permitting current flowing in one Y direction butnot in the other to pass through the winding 2. This device A is auni-directional current-carrying device or asymmetric unit, and it may,for example, be similar to the units shown in an application filed by L.O. Grondahl and-F. H. Nicholson on the 7th day of March, 1922, SerialNo. 541,7 33. This particular typeof asymmetric unitisnot essential'tomy invention, however, itbeing'understood that any unit or device whichwilltrans mit more current flowing in one direction than in the other,will serve the purpose. The direction of high conductivity in the deviceA is indicated by the arrow. A similar asymmetric unit A is associatedwith the winding 3. As here shown, each of these units A and A isconnected in series with the associated winding, and these units are soarranged that current flowing in one direction is permitted to passfreely through winding 2, but not through winding 3, whereas currentflowing in the other direction is permitted to pass through winding 3but not windin 2.

Interposed. between the windings 2 an 3 and controlled thereby, is anarmature con.-

-which, as illustrated, is open. Assumi position wherein contact 45 isclosed..

When winding 3 is energized and winding 2 1s de-energized or energlzedless strongly than winding 3, contact member 4 is swung to the right sothat contact 4-6 is closed. W'hen, however, winding 2 is energized andwinding 3 is tie-energized or energized less strongly than winding 2,the contact member 4 1s swung to the left, so that contact 47 becomesclosed.

It will be seen from the foregoing that when pole-changer 8 occupies oneposition so that current of one polarity is supplied to the windings 2and 3, armature contact 4 is swungin'one direction, whereas whenpolechanger 8 occupies its other position so that current of the otherpolarity is supplied to the windings, armature contact 4 occu'pies itsother extreme position. The apparatus constitutes, therefore, meansresponsive to reversals of-current without the necessity for apermanentmagnet or other polarizing medium. 7

Referring now to Fig. 2, the apparatus shown in this view is similar tothat shown in Fig. 1, except that the two windings 2 and 3 with theirmutually controlled contact member 4 are replaced by two relays 10 and11 provided respectively with contacts 12 and 17. When pole-changer 8 isin one extreme position relay 10 is energized and relay 11 de-encrgized,whereas when pole-changer 8 is in the other extreme position relay 11.will be energized and relay 10 will be de-energized.

In Fig. 2 I have shown means. for at times supplying alternating currentinstead of direct current to the relays 10 and 11, this alternatingcurrent being obtained from the secondary of a transformer 14, theprimary of which is connected with a source of alternating current notshown in the drawing. The secondary of transformer 14 may be connectedwit-h the relays 10 and 11 by a switch }113, t is switch to be closedand pole-changer 8 p aced in the intermediate position wherein battery 9is disconnected from the rest of the apparatus, it will be seen thatalternating current will be supplied to the relays 10 and 11. Duriugone-half of each cycle the asymmetric unit A will permit current to flowfreely through relay 1t), and during the other half of each cycle theasymmetric unit A will permit current to flow freely through relay 11,so that both relays will then be energized. It will be seen, therefore,that in the arrangement of apparatus shown in Fig. 2, one relay 1() orthe other relayl l. or both relays will he energized according as directeurreut of one polarity or direct current-of the other polarity oralternating current is supplied to these relays.

Referring now to Fig. 3. the two relays 10 and 11 are connected inseries instead of multipleas in the preceding views. Relay 10 isprovided with a shunt including an asynimetric unit. A, whereas relay 11is provided with a shunt including an asymmetric unit A. These units areop 'iositely disposed, so that current of one polarity but. not theother is forced to flow through relay 1(),whereas current of the secondpolarity but not the first is forced to flow through relay 11. In thearrangement shown in the drawing, relay 10 is provided with anadditional asymmetric unit A which freely passes the current which isforced by unit A to flow through relay 10, but opposes the passage ofthe flow of current of the other polarity in relay 10. Relay 11 issimilarly provided with an additional unit A' which freely passes acurrent that is forced by unit A to flow through the relay 11 butopposes the passage of current of the other polarity.

As shown in the drawing, the lower terminal of battery 9 is positive, sothat with the pole-changer 8 in the position shown, current will flowthrough asymmetric unit A, relay 10, asymmetric unit VA, and polechanger 8 to battery 9, so that relay 10 is energized and relay 11 isde-energized. When pole-changer 8 is reversed, current will flow frombattery 9, through the pole-changer. then through relay 11, unit A, unitA, and pole-changer 8 to battery 9, so that relay 11 will be energizedand relay 10 will be deenergized. When pole-changer 8 is placed in anintermediate position and circuit controller 13 is closed, alternatingcurrent will be supplied to the relays, so that relay 10 will beenergized durin one-half of each cycle and relay 11 will e energizedduring the other half of each cycle, with the result that both relayswill be closed.

In Fig. 3, it will be observed that relay 10 is provided with a shuntpath including units A and A, which path offers a low resistance tocurrent induced therein by the decay of flux in the relay core when therelay becomes (lo-energized. It follows that when the relay becomesde-energized this path retards the decay of flux in the relay core andso retards the opening of armature contact 12. In other words, this pathgives the relay 9. slew-releasing characteristic, and so has the sameeffectas a closed conductor around the core of the relay. The same thingis true of the path in shunt to relay 11 including units A and A Thesame thing is also true of the relays 10 and 11 in Fig. 2 except that inthis view the resistance of the shunt path for each relay is relativelyhigh because the path includes the other relay, and so the period ofretardation is reduced. In Fig. l each winding 2 and 3 is provided witha shunt path including the other winding and the units A and A, but theetlect in this view is to quickly return armature 4 to it'siuiddleposition when pole-changer 8 is moved to its middle position. becausethe current induced in the shunt path by the winding last energizedserves to energize the other winding for a short interval of time.

Referring again to Fig. 2, and assuming that the pole changer 8 is openand switch 123 closed, when the upper horizontal wire is positive withrespect to the lower, the

current supplied to relay 11 through asymmetric unit A causes apotential drop in the seeondai'y of transformer 14. This potential dropreduces the electromotive force between the two horizontal wires andtherefore relures the potential drop across asymmetric unit A. As aresult the current flowing through unit A in its high resistancedirection and relay 1() is considerably reduced. Similarly, when thelower horizontal wire is positive with respect to the upper wire, thecurrent supplied to relay 10 causes a potential drop in the secondary oftransformer 14 which reduces the current then flowing through unit A andrelay 11. The result of this is that the current through either relay 10or 11 in the'undesired direction is held down to a relatively low value,and so a maximum of useful power is supplied to the load comprisingthese relays. In other words, the

rectifier A in series with relay 11 prevents the supply of an abnormalvoltage to rectifier A, and vice versa. In Fig. 3, when the upperhorizontal wire is positive with respect to the lower,- current issupplied to relay 11 through units A and A, and when the polarity of theelectromotive force is reversed the potential across relay 11 and unit Ais shunted by unit A, thereby preventing an abnormal current in theundersired direction through relay 11. In both Figs. 2 and 3, then, thecurrent through an asymmetric unit in its high resistance direction isdiminished by preventing an abnormal rise of voltage atthe terminals ofthe unit, and this results in a net increase of useful uni-directionalcurrent for a given output circuit including a load and an asymmetricunit without increasing the voltage applied to the circuit. v

Referring now to Fig. 4, the reference characters 15 and 15 designatethe track ltit) I It) rails of a railway along which traflic normallymoves in the direction indicated by the arrows, which rails are dividedby insulated joints 16 into a plurality of successive sections D-E, E-F.etc. Located adjacent the entrance endof each section is a pair ofwindings 2 and 3 connected in multiple across the rails of the section,an asynunetric unit A being included in series with winding 2, and anasymmetric unit A in series with winding 3. These windings mutuallycontrol a contact member 4 as in Fig. 1. Current is reversibly suppliedto the rails of each section adjacent the exit end of the section bymeans of a battery designated 9 with a suitable exponent and apolechauger designated 8 with a suitable exponent, which pole-changermay be operated by any suitable means not shown in the drawing. In orderto simplify the description of the apparatus, I will term the windings 2and 3, the associated asymmetric cells A and A. and the contact member4. a relay device. Each relay device controls a signal designated by thereference character S with an exponent corresponding to the location,each of which signals in the form here shown comprises three electriclamps G, Y and R. These lamps are arranged to pro ject beams of green,yellow and red light. respectively, and when lighted they indr'aterespectively, proceed, caution and stop. The proceed lamp G is providedwith a circuit which passes from terminal B of a suitable source ofcurrent, through contact 47 of the associated relay device to terminal Cof the same source of current. Caution lamp Y is similarly controlled bycontact 4-6, and the stop lamp R is similarly controlled by contact 45of the associated relay device.

As shown in the drawing, the section immediately to the right of point Fis occupied by a train W. so that both of the windings 2 and 3 of therelay device at point 1 are deenergized. Contact 45 being closed. signalS indicates stop. Pole-changer 8 is in such position that the upper railin section EF is positive, so that winding 3 of the relay device atpoint E is energized. Contact 46 of this device is accordingly closed,so that signal S indicates caution. Pole-changer 8 is in such positionthat the lower rail 15 of section DE is positix e, whereby winding 2 ofthe relay device at point D is energized and winding 3 of this device isde-energized. Contact 47 of this relay device is accordingly closed, sothat signal S indicates proceed. \Vhen the train W passes out of thesection immediately to the right of point F, sig nal S will change tothe caution indication and pole-changer 8 will then be reversed, so thatsignal S will change to the proceed indication.

Referring now to Fig. 5, I have here shown a four-indication signalingsystem using the arrangement of relays and asymmetric units shown inFig. 3. That is to say, two relays 10 and 11 are connected in seriesacross the rails at the entrance end of each track section, andassociated with these relays are four units A. A, A and A so arrangedthat current flowing in one direction energizes one relay, whereascurrent flowing in the other direction energizes the other relay.

Each of the signals in the arrangement here shown is of the two-armsemaphore type. and each signal is controlled by the associated relays1t) and 11 in the following manner: \Vhen both relays are (lo-energized(see signal S) both semaphore arms 25 and 26 are in the horizontalposition indicating stop. When relay 11 is energized and relay 10 isde-energized (see signal S a cantion indication circuit is closed forscum-- phore arm 25, which circuit passes from terminal B of a suitablesource 0t. current through contact 21 of relay 11 and operatingmechanism of semaphore 25 to terminal C of the same source of current.The signal then indicates proceed prepared to stop at next signal. Whenrelay 10 is energized and relay ll de-encrgized (see signal S thecaution indication circuit for semaphore arm 25 passes from terminal B,through contact 18 of relay 10, and the semaphore arm operatingmechanism to terminal C. A circuit for semaphore arm 26 is also closed.which circuit passes from terminal B, through back contact 17 of relay11. contact 12 of relay l0 and the operating mechanism of arm 26 toterminal C. The signal then indicates proceed with caution. \Vhen bothrelays 10 and l] are energized (see signal S) the circuit for semaphore.arm 26 is open at back contact 17 of relay 11 but the caution circuitfor semaphore arm 25 is still closed at contact 18 of relay 10. Theproceed circuit for arm 25 is also closed, which circuit passes fromterminal B through contact 19 of relay 10, contact 22 of relay 11, andthe operating mechanism of arm 25 to terminal C. Semaphore arm 25 isthen in vertical position so that the signal indicates proceed.

As shown in the drawing, the section immediately to the right of point His occupied by a train W, so that both relays 10 and 11 at point H areole-energized, with the result that signal S indicates stop. Current isnow supplied to the rails of section FH from the secondary of thetransformer 29, the primary of which is constantly supplied withalternating signaling current from a generator J through the medium of atransmission line 30. The circuit for section Fll is from the left-handterminal of the secondary of transformer 29, through wire 31, the rail15, and from rail 15, through reactance 24, wires 32 and 33, asymmetricunit A, back point of contact 23 of relay 11 and back point of contact20 of relay 10 to the right-hand terminal of the secondary oftransformer 29.

Asyunnetric unit A is so connected in this circuit that current can flowfrom the righthand terminal of the transformer secondary to theleft-hand terminal but not in the other direction, and, consequently,relay 11 at point F is energized and relay at the same point is(lo-energized. The circuit for supplying current to the rails of sectionIl'lF is the same a the circuit for section F-H, except that the currentfor section E-F passes through asymmetric unit A and the front point ofcontact 22%, instead of through unit A and the hack point of contact 23.Consequently. at point F the current can flow from the left haudterminal of the secondary of transformer29* to the right-hand terminalbut not in the other direction. The result of this is that at point Erelay 10 is energized and relay 11 is (lo-energized. The circuit forsuplying current to the rails of section D-E passes from the secondaryof transformer 2!), through wire 31, the rail 15*, and from rail 15through reactance 24, wires 32 and 31, and the front point of contact ofrelay 10 to the secondary of transformer 29 It follows that alternatingcurrent is supplied to the rails of section D-E so that both relays 10and 11 are energized. Alternating current will accordingly be suppliedto the section to the left of point D because relay 10 at point D isenergized.

\Vhen the train \V passes out of the section to the right of point H,relay 11 at point H will become energized, so that at point F relay 11will become de-energzed and relay 10 will become energized. Both relays10 and 11 at point E will then become energized, so that signals S willthen give a proceed indication.

Referring now to Fig. 6, the apparatus here shown is similar to thatshown in Fig. 5, except that the signaling system is of thethreeindication type. That is to say, each signal S is adapted toindicate stop, caution and proceed, and, as here shown, each of thesesignals is of the one'arm semaphore type. Each signal is provided with acaution indication circuit including contact 12 of the associated relay10, and with a proceed indication circuit including contact 17 of theassociated relay 11. It follows that each signal will indicate cautionwhen relay 10 is energized. proceed, when relay 11 is energized, andstop when both of these relays are deenergized.

As shown in the drawing, the section immediately to the right of point Fis occupied by a train W, so that both relays 10 and 11 at point F arede-energized, with the result that signal F indicates stop. The rails ofsection EF are now supplied with current which passes from terminal B ofa suitable source, through back contact 22 of relay 11, back contact 19of relay 10 to lower rail 15*, and from upper rail 15, through backcontact 18 of relay 10, back contact 21 of relay 11 to terminal C of thesame source. This current is in such direction as to energize relay 1Oatpoint E but not relay 11 at the same point. Signal S accordinglyindicates caution, and current is supplied to the rails of section DEfrom terminal B, through front contact 20 of relay 10 to the upper rail15,

and from the lower rail 15 through front contact 27 of relay 10 toterminal C of the same source. This current flows in such direction thatat point D relay 11 is energized and relay 10 is de-energized. Signal Saccordingly indicates proceed, and the supply of current to the rails ofthe section to the left of point D is as follows: from terminal 1"),through front contact 23 of relay 11 to 'rail 15, and from rail 15",through front contact 28 of relay 11 to terminal C. This current flowsin the same directions as that supplied to section DE, so that at thenext point to the left of point D relay 11 will be energized and relay10 de-energized.

Although I have herein shown and described only a few forms of apparatusembodying my invention, it is understood that various changes andmodifications may be made therein within thescope of the appended claimwithout 'departing'from the spirit and scope of'my invention.

Having thus described my invention, what I claim is:

In combination, two windings, asymmetric units associated with saidwindings for permitting currents of one polarity-but not of the other toflow through one winding and for permitting current of the secondpolarity but not of the first to flow through the second winding, meansfor supplying direct current of one polarity or the other to saidwindings to selectively energize one winding or the other, and means forsupplying alternating current to said windings to energize bothwindings.

In testimony whereof I aflix my signature.

PAUL H; GEIGER.

